Description
Split a supplied single IOB tag into prefix and entity-type text.
Language-processing records distinguish tokens, code points, UTF-16 positions and UTF-8 byte offsets. Tag grammars and local transition checks do not validate a full annotation sequence. Log-loss units determine perplexity conversion, while identifier suffixes may be textual labels rather than ordinary decimal numbers.
Split a supplied single IOB tag into prefix and entity-type text.
When to use this tool
Use IOB Entity Tag Prefix Split when you already have tag and need to split a supplied single IOB tag into prefix and entity-type text.
How to use the tool and how it works
- Enter tag. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read prefix, entityType. Use the output convention below.
Accept exact O or B-/I- with a nonempty same-line suffix; reject CR/LF and invalid prefix syntax. O returns an empty entity type; others preserve the suffix after the first hyphen.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| tag | Tag | Required. Text; maximum UTF-16 length 8192. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| prefix | Prefix | Required. Text; maximum UTF-16 length 8192. |
| entityType | Nonempty suffix for B-/I-; whitespace can occur in the suffix but line-separator characters fail the grammar. | Required. Text; maximum UTF-16 length 8192. |
{
"input": {
"tag": "B-PER"
},
"output": {
"prefix": "B",
"entityType": "PER"
}
}Limitations and assumptions
- Spaces and tabs inside a permitted type are not normalized. No tag vocabulary, sequence transition, initial/final state or actual entity is validated.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Alternative or Complementary methods
Validate the complete corpus format, tokenizer, annotation sequence and scoring convention. Use a full parser or model evaluation when needed, preserving the exact offset unit, vocabulary and log base rather than inferring them from a local transformation.
References
Similar or alternative tools
- BIOES Single Token Transition Label
Check one supplied local BIOES tag transition.
- CoNLL-U Decimal Empty Node Key
Split a supplied CoNLL-U-style decimal empty-node ID.